Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!zodiac!spark!medmunds
From: medmunds@Verity.COM (Mike Edmunds x7645)
Newsgroups: comp.windows.x
Subject: Re: Transparent Pixel values
Keywords: Pixmap, Window, Pixels
Message-ID: <9692@zodiac.ADS.COM>
Date: 3 Nov 89 22:44:27 GMT
References: <809@thor.wright.EDU>
Sender: news@zodiac.ADS.COM
Reply-To: medmunds@verity.com (Mike Edmunds x7645)
Organization: Verity, Inc., Mtn. View, CA  94043, (415) 960-7600
Lines: 16

In article <809@thor.wright.EDU> ardatta@odin.wright.edu (Arpita Datta) writes:
>How can I copy objects drawn on the Pixmap, onto the window without
>destroying the tiled background of the window ? 

I've had some success with setting the clip_mask in a GC to a bitmap
with objects drawn on it, and then painting through this "stencil"
using XFillRectangle over the entire area.  Only pixels that were set
in the bitmap are affected in the destination window.  If your
original pixmap was more than one plane deep, you'll have to separate
it into components (I keep a separate bitmap for each color) and paint
multiple times.

If somebody knows of a better way to do this...

- Mike Edmunds
  Verity, Inc.		(All opinions my own)